Carbon nanotubes are very promising nanomaterials. Based on its nano-scale size and special structure, carbon nanotubes have good electrical properties, photoelectric properties and semiconducting properties. In recent years, a carbon nanotube layer composed of carbon nanotubes used as a semiconducting layer has become a popular research direction. When the semiconductor layer is prepared from a carbon nanotube layer, a carbon nanotube array is grown first, and then the carbon nanotube array is directly processed into a layered structure for use as a semiconductor layer. Since the carbon nanotubes can be classified into a metallic type and a semiconducting type, and it is impossible to control the type of the carbon nanotubes when the carbon nanotube arrays are grown. Therefore, the semiconducting layer prepared by this method includes many metallic carbon nanotubes, which will affect the performance of the semiconductor layer.
What is needed, therefore, is to provide a method for making a semiconducting layer that can overcome the above disadvantages.